Mineralogy Database

Montebrasite Mineral Data

Search Webmineral :
  
Advertisment

General Montebrasite Information

Help on Chemical  Formula: Chemical Formula: LiAl(PO4)(OH,F)
Help on Composition: Composition: Molecular Weight = 146.40 gm
   Lithium      4.74 %  Li   10.21 % Li2O
   Aluminum    18.43 %  Al   34.82 % Al2O3
   Phosphorus  21.16 %  P    48.48 % P2O5
   Hydrogen     0.52 %  H     4.61 % H2O
   Oxygen      51.91 %  O
   Fluorine     3.24 %  F     3.24 % F
                 -   %   F    -1.37 % -O=F2    
              ______        ______ 
              100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: LiAl(PO4)(OH)0.75F0.25
Help on Environment: Environment: Forms large-sized crystals in lithium-bearing pegmatites. Species and name natromontebrasite are discredited because natromontebrasite is a mixture of OH-rich amblygonite with lacro ixite and subordinate wardite
Help on IMA Status: IMA Status: Discredited IMA 2005 No. 05-E
Help on Locality: Locality: Montebras, Creuse, France. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for the locality in 1872.
Help on Name Pronunciation: Name Pronunciation: Montebrasite + Pronunciation Say MONTEBRASITE
 

Montebrasite Image

Click Here for Larger   Image in a New Browser Window Images:
Click Here for Larger   Image

  Montebrasite

Comments: Transparent, pale yellow, tabular crystals of Montebrasite on matrix.
Location: Newry, Oxford County, Maine, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Montebrasite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.7269:1:0.7093
Help on Cell Dimensions: Cell Dimensions: a = 5.178, b = 7.123, c = 5.053, Z = 2; alpha = 112.03°, beta = 97.9°, gamma = 67.81° V = 158.45 Den(Calc)= 3.07
Help on Crystal System: Crystal System: Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.968(1), 3.164(0.9), 4.672(0.7),
Help on Forms: Forms:

Mouse
Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize

Keyboard
S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu

Help on Above

Forms: ( 0 2 1) ( 0 1 0) ( 0 2 1) ( 1 1 0) ( 1 0 0) ( 0 0 1)

Warning: this java applet does not work in some browsers because of security restrictions.

 

Physical Properties of Montebrasite

Help on Cleavage: Cleavage: {100} Perfect, {110} Good, {011} Distinct
Help on Color: Color: Bluish, Colorless, Greenish, Greenish gray, Gray white.
Help on Density: Density: 3.027
Help on Diaphaneity: Diaphaneity: Transparent to Translucent
Help on Fracture: Fracture: Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.
Help on Habit: Habit: Massive - Granular - Common texture observed in granite and other igneous rock.
Help on Habit: Habit: Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Help on Hardness: Hardness: 5.5-6 - Knife Blade-Orthoclase
Help on Luster: Luster: Vitreous - Greasy
Help on Streak: Streak: white
 

Optical Properties of Montebrasite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.045 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= 0.049 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.199,KPDmeas= 0.1999,KC= 0.2093
Ncalc = 1.63 - 1.64
Help on Optical Data: Optical Data: Biaxial (-), a=1.57-1.6, b=1.61, g=1.62, bire=0.0200-0.0500, 2V(Calc)=52-88, 2V(Meas)=81.5.
 

Calculated Properties of Montebrasite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.98 gm/cc
note: Specific Gravity of Montebrasite =3.03 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0038058115
Boson Index = 0.9961941885
Help on Photoelectric: Photoelectric: PEMontebrasite = 1.61 barns/electron
U=PEMontebrasite x rElectron Density= 4.80 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Montebrasite is Not Radioactive
 

Montebrasite Classification

Help on  Dana Class: Dana Class: 41.05.08.02 (41)Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen
  (41.05)where (A B)2 (XO4) Zq
  (41.05.08)Amblygonite Group
 
41.05.08.01 Amblygonite (Li,Na)Al(PO4)(F,OH) P1 1
 
41.05.08.02 Montebrasite? LiAl(PO4)(OH,F) P1 1
 
41.05.08.03 Natromontebrasite? (Na,Li)Al(PO4)(OH,F) P1 1
Help on  Strunz Class: Strunz Class: 08.BB.05 08 - PHOSPHATES, ARSENATES, VANADATES
  08.B - Phosphates, etc. with Additional Anions, without H2O
  08.BB -With only medium-sized cations, (OH, etc.):RO4 � 1:1
 
08.BB.05 Amblygonite (Li,Na)Al(PO4)(F,OH) P1 1
 
08.BB.05 Natromontebrasite? (Na,Li)Al(PO4)(OH,F) P1 1
 
08.BB.05 Montebrasite? LiAl(PO4)(OH,F) P1 1
 
08.BB.05 Tavorite LiFe(PO4)(OH) P1 or P1 Tri
 

Other Montebrasite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Montebrasite :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - EUROmin Project
5 - Ecole des Mines de Paris
6 - GeoScienceWorld
7 - Google Images
8 - Google Scholar
9 - Handbook of Mineralogy (MinSocAm)
10 - Handbook of Mineralogy (UofA)
11 - MinDAT
12 - Mineralienatlas (Deutsch)
13 - Online Mineral Museum
14 - QUT Mineral Atlas
15 - Ruff.Info
16 - Scandinavian mineral gallery
17 - WWW-MINCRYST

Search for Montebrasite using:

Google
 
Web webmineral.com
[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Montebrasite :

Ask about Montebrasite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

Print or Cut-and-Paste your Montebrasite Specimen Label here :

Montebrasite

LiAl(PO4)(OH,F)
Dana No: 41.05.08.02 Strunz No: 08.BB.05
Locality:

 

Notes:

 

 
   
 


Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.